math

A man who can swim at 5km/h in still water swims towards the east to cross arriver. If the river flows from north to south at the rate of 3km/h
a) Calculate:
i) The resultant speed
ii) The drift
b) If the width of the river is 30m, find the time taken, in seconds, for the man to cross the river

  1. 👍 0
  2. 👎 0
  3. 👁 494
  1. X = 5 km/h
    Y = -3 km/h

    i. Speed = Sqrt(X^2+Y^2) = sqrt(5^2+3^2)= 5.83 km/h = 1.62 m/s.

    b. Tan A = Y/X = -3/5 = -0.60
    A = -31o = 31o S. of E.

    d = 30m/Cos(-31) = 35 m. = Distance to cross.

    d = V*t = 35 m.
    t = 35/V = 35/1.62 = 21.6 s.

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Math 2

    Juanita runs every 3rd day and swims every 5th day. If Juanita runs and swims today, in how many days will she run and swim again on the same day?

  2. physics

    A swimmer swims in still water at a speed of 6.83 m/s. He intends to swim directly across a river that has a downstream current of 2.89 m/s. (a) What must the swimmer's direction be?

  3. math

    Juanita runs every seventh day and swims every fifth day. If Juanita runs and swims today, in how many days will she run and swim again on the same day? She will run and swim again in ____ days.

  4. Physics

    A river has a steady speed of 0.500 m/s.A student swims upstream a distane of 1.00 km and swims back to the starting point. If the student can swim at a speed of 1.20 m/s in still water, how long does the trip take? How much time

  1. Physics

    A river flows toward the East at 1.5 m/s. Steve can swim 2.2 m/s in still water. If he wishes to cross the river so that his direction is northward, what direction relative to the water must he swim?

  2. Physics

    A man which travel due north in other to cross a river 5km wide flowing due east at 3km/h. If he can roll at 10km/h in still water. Find either by scale drawing or by calculation (1) the direction in which he must head is boat in

  3. Physics

    Vanessa can swim 3.0 m/s in still water. While trying to swim directly across a river from west to east, Vanessa is pulled by a current flowing southward at 2.0 m/s. A) What is the magnitude of Vanessa’s resultant velocity? B)

  4. PHYSICS

    A river is flowing from west to east at a speed of 8m/min, a man on the south bank of the river , capable of swimming at 20m/min in still water, wants to swim across the river in the shortest time. He should swim in a direction of

  1. math

    a man walks 8km north and 5km in a direction east of north.find the distance from the starting point

  2. Math

    Zain goes swimming. He swims the first length of the pool in 2.5 minutes. The time he takes to swim each length is 10 seconds more than he took to swim the previous length. A. Find the time Zain takes to swim the fifth length. B.

  3. science

    a man wishes to swin across a river 600 m wide. If can swim at the rate of 4 km/hr in still water and the river flows at 2 km/hr. Then in what direction must he swim to reach a point exactly opposite to the starting point bnd when

  4. phys

    A long distance swimmer is able to swim through still water at 4km/hr. She wishes to swim from Port Angeles, WA due north to Victoria, B.C., a distance of 50km. An ocean current flows through the Strait of Juan de Fuca from west

You can view more similar questions or ask a new question.